Does anyone use inflatable swimming pools, or any kind of pools for that matter, inside to overwinter fish? I have searched indoor ponds, and see lots of neat ones built but don't want to spend the money on the wood materials. We were thinking of maybe using one of the swimming pools in our basement. We have a cement floor so weight isn't a concern. How big would we have to go for 10 koi (8-15inches) and 1 goldfish? How many gallons would be "ok" without water quality issues? Also, would like to see pictures of different styles etc.